Carlo Lobrano
51bb354624
Currently Dell plugin implements a retry logic of three commands (AT+GMI, AT+CGMI, ATI1I2I3) to detect modem's vendor string. Moreover, since Telit modems always reply to the first command, to speed the probing time up, those modem are tagged with an Udev rule so that we can avoid sending the other two commands at all. However, the retry logic is in case a port needs some time to reply, so it makes sense to apply it only to the first command. Then if the port still does not respond with any kind of reply, that probably means that it is not AT capable and we can skip the other AT commands as well. Then, this patch: - sets a maximum number of timeouts for AT+GMI to 3. After this timeouts, the port is considered not AT-capable. - sets AT+CGMI and ATI1I2I3 to be sent only once. - removes Dell udev rule for tagging Telit Modems.
ModemManager. ModemManager provides a unified high level API for communicating with mobile broadband modems, regardless of the protocol used to communicate with the actual device (Generic AT, vendor-specific AT, QCDM, QMI, MBIM...). Using. ModemManager is a system daemon and is not meant to be used directly from the command line. However, since it provides a DBus API, it is possible to use 'dbus-send' commands or the new 'mmcli' command line interface to control it from the terminal. The devices are queried from udev and automatically updated based on hardware events, although a manual re-scan can also be requested to look for RS232 modems. Implementation. ModemManager is a DBus system bus activated service (meaning it's started automatically when a request arrives). It is written in C, using glib and gio. Several GInterfaces specify different features that the modems support, including the generic MMIfaceModem3gpp and MMIfaceModemCdma which provice basic operations for 3GPP (GSM, UMTS, LTE) or CDMA (CDMA1x, EV-DO) modems. If a given feature is not available in the modem, the specific interface will not be exported in DBus. Plugins. Plugins are loaded on startup, and must implement the MMPlugin interface. It consists of a couple of methods which tell the daemon whether the plugin supports a port and to create custom MMBroadbandModem implementations. It most likely makes sense to derive custom modem implementations from one of the generic classes and just add (or override) operations which are not standard. There are multiple fully working plugins in the plugins/ directory that can be used as an example for writing new plugins. Writing new plugins is highly encouraged! The plugin API is open for changes, so if you're writing a plugin and need to add or change some public method, feel free to suggest it! License. The ModemManager and mmcli binaries are both GPLv2+. The libmm-glib library is LGPLv2+.